Crop protection agents are often administered in the form of aqueous systems. For example, water-based formulations may be obtained by dissolving, emulsifying and/or suspending pesticidally active ingredients in water prior to application. In order to increase their water solubility, active ingredients are often converted into water-soluble salts by reacting them with a suitable base such as alkali or alkaline-earth metals or water-soluble amines, for example.
Mixes of two or more pesticides are commonly prepared by the grower in a process known as tank mixing to take advantage of the properties of each active ingredient. In tank mixing, typically, two or more concentrated formulations are dissolved, emulsified and/or suspended in a larger volume of a suitable carrier, for example, water. For example, at least two fungicides, at least two herbicides, or at least two insecticides may be tank mixed. In some situations, it may also be desirable to tank mix mixtures of fungicides, herbicides, and/or insecticides. Tank mixes are useful, for example, for control or suppression of a broad spectrum of plant pathogens and for control or suppression of plant pathogens exhibiting resistance or tolerance to a particular pesticide. Tank mixing, however, can often be problematic.
For example, commercially available pesticide concentrates often contain adjuvant systems that are carefully metered and/or specific to particular active ingredients. Tank mixing can increase the amount of adjuvants present in the tank, and/or can increase the effects the adjuvant from one product may have on the activity of the active ingredient of another product. As such, tank mixes of different pesticide concentrates can lead to performance issues, such as increased phytotoxicity to the non-target vegetation, e.g. crops, turf or other desirable plants.
Further, tank mixing can lead to compatibility problems. For example, even at low concentrations, tank mixes of two or more water soluble, electrolytic pesticides, can result in compatibility problems.
When concentrated mixtures of electrolytic pesticides are prepared, formulation compatibility is even more likely to be negatively impacted. For example, when trying to prepare concentrated mixes of two or more electrolytic pesticides for commercial sale, phase separation, formation of solid precipitates, or other formulation failures can occur. Similarly, in some instances, when trying to prepare concentrated tank mixes containing two or more electrolytic pesticides for application, phase separation, formation of solid precipitates, or other mixing problems can occur. Additionally, in some instances, tank mixing may result in crop phytotoxicity and/or pesticide antagonism or reduced efficacy. Further, some commercial mixes may formulate initially, but are not suitable for storage and transport.
Various embodiments of the invention are directed to various combinations of these, and additional, problems.